[43] Cell Proliferation and Viability Assays

Question 1

What is cell proliferation?

Answer 1

The process that results in an increase of the number of cells.

Question 2

What is cell viability?

Answer 2

A measure of the proportion of live, healthy cells within a population.

Question 3

What is an assay?

Answer 3

A procedure in molecular biology for testing or measuring the activity of a drug or biochemical in an organism or organic sample.

Question 4

What is the purpose of cell proliferation and viability assays?

Answer 4

To assess cell health, function, and response to treatment in research and drug development.

Question 5

Name three common cell proliferation assays.

Answer 5

• BrdU Assay
• MTT Assay
• WST-1 Assay

Question 6

How does the BrdU assay measure cell proliferation?

Answer 6

It incorporates BrdU, a thymidine analogue, into the DNA of proliferating cells which can be detected using a specific antibody.

Question 7

How does the MTT assay work?

Answer 7

It uses a colorimetric method to measure metabolic activity of cells, which is generally proportional to the number of viable cells.

Question 8

What is a WST-1 assay used for?

Answer 8

For assessing cell metabolic activity, a proxy for cell viability.

Question 9

What are viability assays used for?

Answer 9

To determine the proportion of live cells in a sample, typically following a treatment or environmental change.

Question 10

What is the Trypan Blue Exclusion test?

Answer 10

A method of estimating the number of viable cells present in a cell suspension. It is based on the principle that live cells possess intact cell membranes that exclude certain dyes, such as Trypan blue, whereas dead cells do not.

Question 11

What are the Live/Dead assays?

Answer 11

A method to simultaneously quantify live and dead cells in a cell population based on membrane integrity and esterase activity.

Question 12

What are TUNEL assays used for?

Answer 12

They are used to detect DNA fragmentation resulting from apoptotic signaling cascades.

Question 13

What is apoptosis?

Answer 13

A form of programmed cell death that occurs in multicellular organisms.

Question 14

What is necrosis?

Answer 14

A form of cell injury which results in the premature death of cells in living tissue.

Question 15

What is flow cytometry used for in the context of cell proliferation and viability?

Answer 15

To provide a fast and quantitative measurement of cell proliferation and viability.

Question 16

How does the ATP assay measure cell viability?

Answer 16

By detecting the amount of ATP present, which indicates metabolically active cells.

Question 17

How does the LDH leakage assay measure cell viability?

Answer 17

By detecting the amount of LDH released from the cell, which indicates cell membrane damage.

Question 18

What is the difference between cell proliferation and viability assays?

Answer 18

Proliferation assays measure the number of cells that are actively dividing, while viability assays measure the number of live, metabolically active cells in a population.

Question 19

What is the significance of cell proliferation and viability assays in drug development?

Answer 19

They are critical for assessing the effectiveness of a drug or treatment and its toxicity on cells.

Question 20

Define LDH.

Answer 20

Lactate dehydrogenase, an enzyme found in nearly all living cells and released into the cell culture medium following loss of membrane integrity.